1. Field of the Invention
The field of the present invention is that of turbine engines and in particular compressors of these turbine engines.
2. Description of the Related Art
Aeronautical turbine engines conventionally consist of a group of assembled modules comprising, in the air circulation direction, one or more compressors, a combustion chamber, one or more turbines which drive the compressor or compressors via drive shafts by extracting power from the gas leaving the combustion chamber, and at the outlet either a nozzle into which the burned gasses are ejected to produce thrust or a free turbine which recovers the energy from the gas to produce mechanical power.
The compressors are conventionally either of the axial flow type where the air flows through them in a substantially axial direction from the inlet to the outlet, or of the centrifugal type where the air enters axially to emerge in a radial direction. In the case of a centrifugal compressor, the air is collected at the impeller outlet by a radial part called a diffuser, then transferred to a second part called a guide vane which returns the compressed air flow to a substantially axial direction before it is introduced into the combustion chamber.
Several configurations have been proposed for these parts on existing aeronautical turbine engines. Engines are known in which the guide vane consists of a part used in combination with the external compressor housing to form a duct to guide the flow. This type of guide vane has the drawback of an imperfect connection between the diffuser and the guide vane and a poor quality of seal at the guide vane.
Monoblock guide vanes are also known which are bolted to flanges linked to the structure of the engine, but these configurations are characterized by additional parts, which entails a penalty in terms of mass. Also these flanges can deform under the effect of vibration or thermal expansion and not ensure perfect continuity of the stream between the diffuser and the guide vane.
Finally monoblock guide vanes are known which are mounted directly onto the diffuser by a hooping type connection which joins the two parts rigidly. Hooping is the assembly of two parts by a shrink fit. The assembly is produced with machining tolerances which prevent its manual assembly or even assembly on a press, and generally means are required for heating or cooling the parts to be assembled. Although this solution brings a benefit in terms of mass and continuity of the stream, it is difficult to disassemble without suitable means and the solution cannot be produced by an operator equipped with conventional tooling only.